This invention relates generally to camera shutters and more particularly to an exposure time control circuit for a camera shutter.
Camera shutter control circuits are well known. These known circuits are constructed with a change-over switch that is operable to one position for operation of the control circuit in which the exposure time is automatically controlled as a function of the intensity of the light received by a light-responsive element in the circuit. The change-over switch is operable to a second position in which a light-intensity indicating circuit is selectively placed in circuit with the light-responsive element so that light readings can be taken for properly setting the shutter speed.
These known circuits have a serious problem in that the existance of the change-over switch introduces a reliability factor in controlling the exposure time. That is the reliability of the change-over switch may affect the two modes of operation.